Why do Gmail and Yahoo recipients show as using an 'Unknown' platform in the Mailing Overview report?

Google and Yahoo have each made changes over the last few years that significantly affected the way images are displayed in their email clients. The major change is that they now cache your email's images on their own servers. All images are now served through the company's servers, rather than through each recipients' individual host server. This has a few major implications for your campaign reports:

The reported IP addresses for your Gmail and Yahoo contacts will be of the company's servers rather than that of your recipient's actual IP address.

Since all campaigns are showing as opened on the company's server, Delivra has no way of knowing what device, such as mobile or desktop, was used to open your campaign. Gmail and Yahoo recipients who show as the following:

Browser: Google Mail or Yahoo Mail

Platform: Unknown

Reading Environment: Web

The above is true because Delivra, like most email marketing systems, uses the images in your content files for tracking purposes.

For more information regarding these changes, please see Litmus' blogs detailing the changes: